Leak spoils NASA’s attempt to launch moon rocket; Next try in a few weeks

CAPE CANAVERAL, Florida (AP) – NASA’s New Moon rocket caused another dangerous fuel leak Saturday, forcing launch controllers to call off their second attempt this week to send a crew capsule into lunar orbit with test dummies. The inaugural flight is now off for weeks, if not months.

Monday’s previous attempt to launch the 322-foot (98-meter) Space Launch System rocket, the most powerful rocket NASA has ever built, was also troubled by a hydrogen leak, although it was smaller. That was on top of the leaks discovered during the countdown drill earlier in the year.

After a recent setback, mission managers decided to pull the missile from the platform to the hangar for further repairs and system upgrades. Some work and testing can be done on the platform before moving the missile. In either case, several weeks of work will be required, according to officials.

With a two-week launch blackout looming in just a few days, the missile has now been grounded until late September or October. NASA will work around a high-priority SpaceX astronaut’s flight to the International Space Station scheduled for early October.

NASA Administrator Bill Nelson stressed that safety is the top priority, especially on a test flight like this where everyone wants to check out the rocket systems “before we put four humans on top of it.”

“Just remember: We won’t shoot until it’s all right,” he said.

NASA is already waiting years to send the crew capsule atop the rocket around the moon. If the six-week demo is successful, astronauts could fly around the moon in 2024 and land on it in 2025. The last time people walked on the moon was 50 years ago.

Launch Director Charlie Blackwell Thompson and her team had just begun loading nearly a million gallons of fuel into the SLS rocket at dawn when the massive leak occurred in the engine section below.

Ground controllers tried to connect them the way they handled previous smaller leaks: stopping and re-flowing supercooled liquid hydrogen in hopes of bridging the gap around the plug in the supply line. They’ve tried it twice, in fact, and they’ve also washed helium through the line. But the leak continued.

Blackwell Thompson finally stopped the countdown after three to four hours of futile efforts.

Expedition Director Mike Sarafin told reporters it was too soon to know what caused the leak, but it may have been due to unintended excessive pressure on the hydrogen line earlier in the morning when someone sent commands to the wrong valve.

“This was not a manageable leak,” Sarafin said, adding that the leaked hydrogen exceeded flammability limits two or three times.

During Monday’s attempt, a series of small hydrogen leaks appeared there and elsewhere on the rocket. Technicians tightened the fixtures over the following days, but Blackwell-Thompson cautioned she wouldn’t know if everything was tight until Saturday’s refueling.

Hydrogen molecules are extremely small – the smallest in existence – and even the smallest gap or slit can provide a way out. NASA’s space shuttle, now retired, has been plagued by hydrogen leaks. The New Moon rocket uses the same type of main engine.

The biggest problem on Monday was that the sensor indicated that one of the rocket’s four engines was too warm, although engineers later verified that it was cold enough. The launch team planned to ignore the faulty sensor this time and rely on other tools to ensure each main engine was properly cooled. But the countdown did not reach that far.

Thousands of people who jammed the coast over the long Labor Day weekend, hoping to see a Space Launch System rocket, left disappointed.

The $4.1 billion test flight is the first step in NASA’s Artemis program to explore the regenerative moon, named after Apollo’s twin sister in Greek mythology.

After years behind schedule and billions over budget, Artemis aims to establish a sustainable human presence on the moon, with crews eventually spending weeks at a time there. It is considered a training ground for Mars.

Twelve astronauts walked on the Moon during the Apollo program, the last time in 1972.

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